Ferroconcrete reinforcement section



Jan. 3, i 5Q N cK FERROCONCRETE REINFORCEMENT SECTION Filed April '7, 1937 b-Zd-Zb 7/ y X Z M da m Mk 5% Patented Jan. 3, 1939 PATENT OFFICE FERROCONCRETE REINFORCEMENT SECTION Andrea. Ossoinack, Vienna, Austria Application April 7, 1937, Serial No. 135,563 In Austria May 6, 1936 3 Claims.

This inventionrelates'to ferro-concrete reinforcement sections, and to the manufacturing thereof.

It is already known to make reinforcing ele- 5 ments for ferro-concrete work, which consist of two round section iron bars twisted up together under tension. Reinforcing elements of this type, however, have but poor inherent rigidity, and when subjected to'compression strains in 10 their length are apt to gape, for which reason they have not hitherto been employed in cases in which the reinforcement is subjected to longitudinal compression strains.

It is also known to make reinforcing elements 5 from iron rods twisted in themselves. These reinforcing elements, however, have poor improving or strengthening qualities, since a considerable proportion of the bulk of the material is concentrated near the axis of twist. It has it is true also been proposed to make reinforcing elements of this type with the bulk of the material disposed remote from the axis of twist, that is to say with a cross-section of dumb-bell shape, but reinforcing sections of this type have but slight lateral rigidity in their weak web, with the result that the twisting operation -is apt to bring about deformation and to set up internal strains and stresses that are not susceptible of detection or checking.

30 It is the object of the invention to provide a reinforcing element consisting of a single iron bar, and to give this bar such shape that it conibines the advantages of a reinforcing element consisting of two rods twisted up together, with 35 the advantages of a unitary reinforcing rod suitable for use under conditions involving longitudinal compression strain. I

In accordance with the invention the reinforcing element consists of a suitably drawn- 40 twisted flat iron section (or flattened round section) of which the cross-sectional breadth is substantially equal to twice the cross-sectional height, and which is longitudinally grooved or channeled on both sides in the vertical mid plane,

45 so that the cross-sectional configuration of the element is substantially the same as that of two circles touching or merging with each other.

In the acc mpanying-drawing forming part of this speclflcation:--

50 Fig. 1 shows in cross-section the' lgnown type of reinforcing elements consisting of two round sections twisted up together.

Figs. 2 and 3 show cross-sections of two erabodiments of the invention, by way of example. '5 Referring to Fig. 1 it can be seen that the breadth b of the known reinforcing element consisting of two round section iron bars twisted up together is twice the height h of the element considered as a whole, or equal to twice the diameter of one of the constituent round section 5 iron bars.

From Fig. 2 it may be seen that the reinforcing element according to the invention, which consists of only a single bar, has substantially- V the same cross-sectionalproportions. Here again the breadth b is twice the height h of the reinforcing bar. The preferred method of manufacturing this novel type of section for reinforcing elements is to roll out the main section on the usual type of roll train employed for rolling round sections, and to use for the last set of the train rollers which are so profiled that the initially round section iron of pre-determined diameter is rolled fiat, until its height is approximately the same as the diameter of one of theround sectionsshown in Fig. 1 and its breadth equal to the breadth of the reinforcing element shown in Fig. 1 (twice the height) In this flattened out round section continuous longitudinal grooves are then rolled on both sides in the vertical mid plane. In the form of construction shown in Fig. 2 the grooves are of triangular cross-sectionand have fiat delimiting surfaces.

It isfequally possible to provide these grooves with cylindrical surfaces so that the cross-sectional configuration of the rolled bar conforms more closely to that of the composite element made of two round section rods shown in Fig. 1.

It is also possible, as shown in Fig. 3, to make these longitudinal grooves of trough-shaped section, without departing from the spirit and scope of the invention.

What is essential for the invention is merely that the bulk of the material to be twisted should be as remote as possible from the axis of twist.

At the same-time the cross-section must be as compact as possible, so that there is no danger of distorting the web during the twisting operation, and so that compression forces may reliably be resisted by the bar.

ments consisting of two round section rodssseeing that in the twisting operation the strengthening 5 is dependent on the stretch, and this latter in its turn on the distance of the particles oi! the pass from the axis of twist.

A particular advantage of the reinforcing element according to the invention is that the commonly used tables of sections and dimensions may perfectly well be used, since the dimensions of the sections according to the invention are proportional to those of the known sections. A further advantage resides in the fact that the new section may be used to replace such thin round sections as could not hitherto be replaced by the use of two round sections twisted up together for the reason a that the diameter of each of these twisted up round sections would otherwise be too small.

I claim:

1. A reinforcing element for ferro-concrete structures which comprises a drawn and twisted bar having a somewhat flattened cross section such that the width of the section is substantially twice the cross-sectional height, said bar having a continuous longitudinal groove on each of the main faces of the bar, said groove being disposed in substantially the mid plane so that the crosssectional configuration of the bar corresponds somewhat with that of flattened merging circles.

2. A reinforcing element for ferro-concrete structures which comprises a drawn and twisted bar having a compact somewhat flattened cross section such that the width of the section is substantiaiiy twice the cross-sectional height, said bar having a continuous longitudinal angular or V-shaped groove on each of the main faces of the bar, said grooves being disposed in substantially the mid plane so that the cross-sectional configuration-ot the bar corresponds somewhat with that of flattened merging circles.

3. A reinforcing element for ferro-concrete structures which comprises a drawn and twisted I ANDREA OSSOINACK. 

